COMPARISON OF THREE STATISTICAL METHODS FOR ESTIMATING WEIBULL PARAMETERS FOR WIND ENERGY ANALYSIS

There is a crucial need in the mainland regions of Nigeria to enhance the development of wind technology and engineering, which is essential for the designing of Wind Energy Conversion Systems (WECS). The Weibull Probability Density Function (PDF) with two parameters is widely accepted and commonly utilized for modelling, characterizing and predicting wind resource and wind power, as well as assessing optimum performance of WECS. Therefore, it is paramount to precisely estimate the scale and shape parameters for all regions or sites under observation. In this research, the daily wind data obtained from measurements covering 11 years (2000 to 2010) for four different locations (Port Harcourt, Ikeja, Kano and Jos) was analysed and the Weibull parameters determined. Three methods are presented for estimating Weibull parameters (Shape and Scale) namely; Mean Standard Deviation Method (MSDM), Energy Pattern Factor Method (EPFM), Method of Moments (MOM), and the method that gives more accurate estimation for the Weibull parameters was Energy Pattern Factor Method (EPFM). Of the three methods, MSDM gave the closest and accurate value of the wind speed for all the stations followed by MOM and then EPFM. In  terms of distribution, EPFM gave a better performance compared to the others, followed by MOM and MSDM respectively.